From New World Encyclopedia

Lying is telling or writing or otherwise promulgating a false statement or claim with intent to deceive. Here we will be concerned only with lies as statements—not lies of demeanor or costume or some other such non-verbal non-veridical appearance or presentation. The existence of lies is dependent on the existence of truth and on the ability to discern or discriminate truth from falsehood.

From antiquity, lying has often been rejected and even condemned by religious figures, by God or the gods (as people have represented God or the gods), by philosophers, by jurists, and others. One of the Ten Commandments, for example, forbids "bearing false witness," meaning giving or promulgating a lie or deliberate falsehood in a juridical or evidence-giving context (Exod. 20:16). That prohibition would presumably also apply to such things as falsifying data in a scientific or engineering situation. Lying when under oath (in a judicial proceeding or similar legal context), even to achieve some greater good, is itself the crime of perjury, and is subject to criminal penalties. Lying to government investigators, even if there is no underlying crime, has often resulted in people being prosecuted for that crime of lying although the supposed crime that was being investigated had not actually occurred.

Despite all those received condemnations of it, lying and the possibility that it may not always be wrong are of considerable interest to ethicists, philosophers, theologians, politicians and others because, at least prima facie, there are cases when lying seems to be preferable, ethically and otherwise, to telling the truth.

Intent to Deceive

Not every falsehood is a lie. Lying requires correct or accurate knowledge of the truth on the part of the giver, and it also depends on the intent with which the falsehood is given. In order for a falsehood to be a lie the person giving it needs to know that it is false, and it must be given with intent to deceive. If the person making the statement thinks or believes that it is true, but it is in fact false, then it is not a lie. Since lying requires that the statement given be false, understanding and discussing lying is parasitic on the existence of truth and on that truth being discoverable.

Absolute Prohibitions Against All Lying

Some writers have strictly forbidden all lying. This has often but not always been done on a religious basis. The writer of the Book of Revelation in the Bible, for example, claims that the one who sits on the throne [of heaven] declared: “But as for the cowardly, the faithless … murderers, fornicators … and all liars, their lot shall be in the lake that burns with fire and sulphur, which is the second death” (Rev. 21:8, italics added).

Saint Augustine rejected all lying for what were religion-based reasons. In the Enchiridion he wrote:

…it is evident that speech was given to man, not that men might therewith deceive one another, but that one man might make known his thoughts to another. To use speech, then, for the purpose of deception, and not for its appointed end, is a sin. Nor are we to suppose that there is any lie that is not a sin, because it is sometimes possible, by telling a lie, to do service to another.[1]

Note that Augustine recognized that, for consequential reasons, it might be preferable sometimes to lie because doing so leads to doing a service to (or for) another person. Yet Augustine rejected such a consequentialist defense of lying because lying, he held, is nevertheless a sin, and sin must always be avoided.

British theologian-evangelist John Wesley similarly rejected consequentialist justifications of lying on the basis that a lie is a sin and sin cannot be condoned even if it leads to good. In one of his sermons he declared:

If any, in fact, do this: either teach men to do evil [so] that good may come or do so themselves, their damnation is just. This is particularly applicable to those who tell lies in order to do good thereby. It follows, that officious lies, as well as all others, are an abomination to the God of Truth. Therefore there is no absurdity, however strange it may sound, in that saying of the ancient Father “I would not tell a willful lie to save the souls of the whole world.”[2]

Wesley thus wholly embraced the seeming contradiction of rejecting the sin of telling a lie even if doing so would lead to universal salvation; he claimed that this is no contradiction and no absurdity, even though most other people would not agree with him on this.

German philosopher and ethicist Immanuel Kant also rejected all lying even though lying might lead to good consequences because Kant rejected consequentialism itself. Kant did this on the basis of his notion of the status of human rationality and his view that rationality is directly connected with human dignity. To lie to a person, Kant claimed, is to offend against that person’s rationality and dignity and also to offend against the rationality and dignity of the one giving out the lie. Thus a lie is always wrong in Kant's view even though it may seem to lead to good consequences. In Doctrine of Virtue Kant wrote, “By a lie a man throws away and, as it were, annihilates his dignity as a man.”

Mental Reservation as a Response to Absolute Prohibitions of Lying

When there is an absolute prohibition against something that people strongly want or think they need to do, then creative ways of circumventing the prohibition will be found. The absolute prohibition against lying within Roman Catholicism led to the formation and use of the doctrine of “mental reservation.”

Common Roman Catholic teaching holds that a lie is intrinsically evil and that an evil thing may never be done in order that a good may result from it, so it is never permissible to tell a lie even if doing so saves a human life. But we are, the teaching holds, also obliged to keep secrets faithfully, and sometimes the best way to do that is to tell a lie. Many writers, ancient and modern, have accepted this, and have thus held that when there is a conflict between doing what is just and telling the truth, justice should prevail. The theory of mental reservation was formulated to give a means whereby the demands of both veracity (truth telling) and justice (what is ethically required) can be satisfied.[3]

There are two versions of mental reservation: the doctrine of wide mental reservation and the doctrine of strict mental reservation.

The Doctrine of Wide Mental Reservation

St. Raymond of Peñafort first broached the doctrine of mental reservation. In his Summa (1235) he quoted St. Augustine's claim that a person must not slay his own soul by lying in order to preserve the life of another, and that it would be perilous to hold that we may do a less evil to prohibit another person doing a greater evil. Raymond then adds:

I believe ... that when one is asked by murderers bent on taking the life of someone hiding in the house whether he is in, no answer should be given; and if this betrays him, his death will be imputable to the murderers, not to the other's silence. Or he may use an equivocal expression, and say 'He is not at home,' or something like that. And this can be defended by a great number of instances found in the Old Testament. Or he may say simply that he is not there, and if his conscience tells him that he ought to say that, then he will not speak against his conscience, nor will he sin.[3]

This stratagem is based on the speaker saying something equivocal or qualified in such a way that what he says is not strictly false. Expressions such as "He is not at home" were called equivocations, or amphibologies, and when there was a good reason for using them everyone admitted their lawfulness. Equivocations and amphibologies came to be called mental restrictions or mental reservations. Sometimes the special circumstances of the speaker led to such necessary equivocations. So, for example, if a confessor (priest hearing confessions) is asked about sins made known to him in confession, he should answer "I do not know," and such words as those when used by a priest mean "I do not know apart from confession," or "I do not know as man," or "I have no knowledge of the matter which I can communicate."

Catholic writers hold that when there is reason to do so, such expressions may be used and they are not lies. The hearer may understand such expressions in a sense that is not true, but the self-deception of the hearer may be permitted to the speaker if there is a sufficiently good reason to do so; but if there is no good reason, then the speaker must speak frankly and openly so that he is correctly understood. It is a sin, Catholic writers hold, to use a mental reservation without a just cause or in a case where the questioner should be told the unreserved truth.

The Doctrine of Strict Mental Reservation

In the sixteenth century, largely because of the difficult political circumstances due to the wars of religion, there was a further development of the mental reservation doctrine.

Martin Aspilcueta, or "Doctor Navarrus" as he was called, was nearing the end of his life and was regarded as being the foremost living authority on canon law and moral theology. He was consulted about a case based on these terms:

Titius, who privately said to a woman "I take thee for my wife" without the intention of marrying her, answered the judge who asked him whether he had said those words that he did not say them, understanding mentally that he did not say them with the intention of marrying the woman.[3]

Navarrus drew up an elaborate opinion on the case and dedicated it to Pontiff Gregory XII. Navarrus maintained that Titius had not lied, not committed perjury, and not committed any sin at all, on the supposition that Titius had a good reason for his answer.

This theory became known as the doctrine of strict mental reservation. In strict mental reservation the speaker mentally adds some qualification to the words he actually says, so that the words together with the mental qualification make a true factual assertion. But in a wide mental reservation, the qualification comes from the ambiguity of the words themselves, or from the circumstances of time, place, or person in which they are uttered.

Navarrus's opinion meant that such strict mental reservations are actually lies because a person tells a lie when he makes use of words that are false with the intention of deceiving another person, and strict mental reservation is based on an intent to deceive and uses words at variance with the truth as it is known to the speaker. Thus strict mental reservation constitutes a lie. The doctrine of strict mental reservation was debated both pro and con for some time, and was finally condemned by Pope Innocent XI on March 2, 1679 (propositions 26, 27). Since the time that this condemnation of the doctrine was issued, Catholic theologians have not defended strict mental reservations.

Consequentialist or Utilitarian Response to the Problem of Lying

A consequentialist or utilitarian—one who claims that the right or good deed or choice or rule is the one that will yield the overall best consequences or greatest good or happiness for the greatest number of people—has no problem with justifying or sanctioning lying if doing so yields better results than telling the truth. In fact, a consequentialist would consider Kantian nonconsequentialism's very rigidity on this point to constitute its own self-refutation: Any position such as Kant's or any other absolutist one that claims that consequences don't count for ethical evaluation cannot be correct because such a position inevitably leads to absurdity (as expressed in the quote above from Wesley) because causing a greater or evil (someone's death) to avoid doing a smaller evil (lying) is unjust.

Justifications of lying are based on rejecting ethical absolutism or nonconsequentialism and accepting a consequentialist stance. Winston Churchill, the British prime minister, gave such a consequentialist justification of lying in a wartime context when told his cabinet, "The truth is so precious that it must be protected by a bodyguard of lies."

No one, however, likes to be lied to. If a hearer is asked whether it is permissible that he or she be lied to in order to prevent or forestall a greater evil, the hearer is nearly always likely to say that the answer is no, so no one should deceive himself or herself by saying that a lie is a small or inconsequential or minor thing. Thus any claim that lying is sometimes justified must be based on strong evidence that deceiving a hearer or hearers will, in fact, actually result in a lesser evil or harm than the harm caused by the lie.

One example of a kind of lie that is widely practiced and widely justified is the use of placebos by doctors. It has been well-established that placebos are often effective remedies for some diseases and or some patients. Placebos are pills or injections that do not have any active drug in them, but that work through their psychological effect because the patient thinks he is receiving a real or genuine drug and thus is at least partly cured because of this belief. The efficacy of the placebo requires, of course, that the patient not learn that he is receiving a placebo instead of a genuine drug; in other words the cure depends on continuing the deception or lie. There are cases in which a patient has learned that he or she was receiving only a placebo and has been highly upset and thus harmed by this revelation.

The harm that comes when a patient discovers that he has been given a placebo is symptomatic of the harm that frequently comes when someone is caught lying for what the giver of the lie thinks are good reasons. They may be good reasons prima facie, but those supposed good reasons are likely to evaporate if the lie is discovered and the fact that it is a lie is broadcast or spread to a larger public. In such a case the harm caused by the lie when the lie is exposed is frequently greater than the harm that giving out the lie was intended to forestall.

Sissela Bok on Lying

The most thorough and nuanced philosophical investigation of lying was done by Harvard philosophy professor Sissela Bok in her book Lying: Moral Choice in Public and Private Life (1978). In that book she discussed a great range of issues and questions connected with lying: The question whether the "whole truth" is attainable; truthfulness, deceit, and trust; whether the standard should be never to lie (as Augustine and Kant held); the role of consequences and how to weigh them; so-called white lies and their variations; excuses; justifications for lying; lies told in a crisis (such as war and threats to survival); lying to liars (in order to unmask them or for other reasons); lying to enemies; lies protecting peers and clients; lies for the public good; deceptive social science research; paternalistic lies; and lies to the sick and dying. An Appendix to her book contains excerpts on truth and lying from works by Augustine, Thomas Aquinas, Francis Bacon, Hugo Grotius, Immanuel Kant, Henry Sidgwick, Roy Harrod, Dietrich Bonhoeffer, and G. J. Warnock.

Bok expresses a great deal of skepticism about supposed justifications for lying, although she does not reject lying entirely. In the conclusion to one of her chapters she writes:

Wherever lies to the public have become routine ... very special safeguards should be required. The test of public justification of deceptive practices is more needed than ever. It will be a hard test to satisfy, the more so the more trust is invested in those who lie and the more power they wield. Those in government and other positions of trust should be held to the highest standards. Their lies are not ennobled by their positions; quite the contrary. Some lies—notably minor white lies and emergency lies rapidly acknowledged—may be more excusable than others, but only those deceptive practices which can be openly debated and consented to in advance are justifiable in a democracy.[4]

Bok concludes by saying that deceptive practices are not immutable, although they cannot be wiped out entirely in an imperfect world. She claims that the justifications invoked for them are often insubstantial, and that they "can disguise and fuel other wrongs." "Trust and integrity," she writes, "are precious resources, easily squandered, hard to regain." Trust and veracity can thrive, she says, "only on a foundation of respect for veracity."[5]


  1. Quoted in Sissela Bok, Lying: Moral Choice in Public and Private Life (New York: Pantheon Books, 1978; 2nd ed, New York: Vintage Books, 1999, ISBN 0394413700).
  2. Quoted in Bok.
  3. 3.0 3.1 3.2 For more information, see the Catholic Encyclopedia article on "Mental Reservation" by T. Slater. Retrieved October 25, 2016.
  4. Bok, 181.
  5. Bok, 249.

ISBN links support NWE through referral fees

  • Augustine, and Henry Paolucci. The Enchiridion on Faith, Hope, and Love. South Bend, IN: Regnery/Gateway, 1961. ISBN 0895269384
  • Bok, Sissela. Lying: Moral Choice in Public and Private Life. New York: Pantheon Books, 1978. Second edition, New York: Vintage Books, 1999. ISBN 0394413700
  • Kant, Immanuel. "On a Supposed Right to Lie from Benevolent Motives," The Critique of Practical Reason and Other Writings on Moral Philosophy (pp. 346-350). Edited and translated by Lewis White Beck. Chicago: University of Chicago Press, 1949.
  • Kant, Immanuel. "The Doctrine of Virtue," part 2 of The Metaphysics of Morals. Translated by Mary Gregor. New York: Harper & Row, 1964. Also: Cambridge & New York: Cambridge University Press, 1996. ISBN 0521562171; ISBN 0521566738
  • Mill, John Stuart. Utilitarianism. Edited by Oskar Piest. Indianapolis, IN: Bobbs-Merrill, 1957.

External links

All links retrieved November 4, 2022.

General Philosophy Sources


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